Finding the Fourth Proportional to 1,013.88, 1,397.72 and 765.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,013.88 : 1,397.72 = 765.48 : x
2. Step 2: Convert to fraction form
   1,013.88/1,397.72 = 765.48/x
3. Step 3: Cross multiply
   1,013.88x = 1,397.72 × 765.48
4. Step 4: Simplify right side
   1,013.88x = 1,069,926.71
5. Step 5: Solve for x
   x = 1,069,926.71/1,013.88
6. Step 6: Final answer
   x = 1,055.28